Change {Combobox,Textfield}ForInput() to {Combobox,Textfield}ForType() so a
pointer to the newly created Combobox (after country change) is easy and safe to
get.

BUG=317837
R=estade@chromium.org

Review URL: https://codereview.chromium.org/101913009

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@242249 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 242249